Measured-service telephone system



Nov. 15, 1927. 1,649,430 J. WICKS MEASURED SERVICE TELEPHONE SYSTEM Original leis uly 9. 1923 3 eets-Sheet 1 JZzm M51;

Nov. 15, 1927.

J. wlcKs MEASURED SERVICE TELEPHONE SYSTEM Inu5n UI'' JUZ'LTL M J. WICKS MEASURED SERVICE TELEPHONE SYSTEM Nov. 15, 1927.

3 Sheets-Sheet 3 Original Filed July '9 1923 Inusn ur Patented Nov. 15,1927.

, 1,649,430 i neural) sr r s" PATENTQOFFICE.

JOHN WICKS, or can rAnK, runners, AssIGNoR, BY rvinsnniassienmnnrs, 'ro Aura. MATIG ntncraic Inc, or cnmaea rimnors, coaronn'rron OF DELAWARE.

MEASURED-SERVICE rnLnrnonn SYSTEM.-

Application filed 1111319, 1923, Serial The present invention relates in general to measured service telephone systemsibut more particularly methods of providing 111: automatic telephone to John WicksNovembcr' 27, 1923. 'The' principal 0b ect of the invention in the instant case is the provision oi improved means for controlling paystation mechanisms of well known type to automatically collect or refund deposited coins; and of improved means whereby the paystations may be controlled by operators in special cases as where a. subscriber'calls a long distance operator and s connected d rectly Wltll.

another subscriber in a distant exchange, this type of connection being commonly re terred to as a two number call.

A further object of the invention is the provision of circuits for permitting subscribers of party lines," equipped with the above type of paystation equipment, to call back on their own line without the aid or intervention of an operator, such parties being given; free service when 'calling par-i ties on their own line. I

Referring now to the drawings, Figs. 1, 2 and 3, when arranged in order with their corresponding lines from a calling substation A to a recording operator in a distant exchange.

Theequipment shown in Figs. 1 and 2' is in the exchange in which the substation A is located, while the equipment, in Fig. 3 is located in the distant. exchange.

Referring to Figfl, thesubstation A is one of four such substations and is-provi'ded with the usual talking apparatus and an automatic calling device or impluse sender S, and being on apaystation line is also pro vided with a well known type of coin collecting apparatus It will be understood that the remaining substations on the line, of which only the ringers are shown, are provided with apparatus identical with that of substation A. V

The line switch C, in. which the line of substation Afterminates', is a rotary line switch or one in which the wipers have 'no normal position but move in a forward direction only. 3

The paystation coin control repeater D or controlling pa'ystation equipment Snob at the ends thereof in alignment, represent a complete 0011116811011 No. ceases. Renewedi'npri l 2-1, 1927,}

that used at the substation A on both local and long distance calls, and in addi tion is provided with means for permitting subscribers of party lines, such as .a subscriber at substation A, to set up connections to other subscribers on-the same line.

The selectors'E and E (Fig. 2) are of the well known Strowger type and are wired inv accordance with the usual two wire practice.

The secondary trunk repeater F is arranged to provide a holding circuit for whatever selector seizes it and is used primarily to avoid the necessity of having three conductors in the trunk line extending to the toll ofiice, but in addition is'provided with coin control circuits.

The relay group H in which the recording trunk Z terminates in thetoll office, has associated with it the jack J at a toll record- 'ing operators position. The operation or" the circuits of the relay group H will be fully described later. i

The cord circuit 0 toll recording operator as well as for completing toll connections. I I

The apparatus having been described in general, a detailed description of its operation will now be given. For this purpose it is assumed that the isubscriber at substation 'A desires atoll connection. In order to initiate such a call he must first call the toll recording operator who then takes care of the call and sees to it that the desired connection. is established. hen the subscriber at substation A removes his receiver, a circuit is completed over the line conductors 1 and 2 for the line relay of the line swi ch C. Upon energizing, line relay 7 closes at its armature 8 a. circuit for the switching relayB and the stepping magnet 10 in series. and at its'armat-ure 9 connects atest wiper 12 t0 the above circuit at a. point between the switching relay and the stepping magnet. The operation now depends upon whether the trunk line upon which the wipers ot' the (Fig. 3) is one that is used for answering calls coming into the line switch are standing is busy or idle. If I the trunk line is busy there is a ground povance the switch wipers in search of idle 3, upper winding of polarized relav gized, the switching relay 3 is not short circuited and the stepping magnet .is not operated because of the high resistance of the switching'relay. The switching relay however is energized grounds the test wiper 12 at armature 5 and at its arinatures 4 and G disconnects line conductors 1 and 2 from the winding of line relay 7 and from ground respectively, and extends them by way ot wipers 11 and 13, contacts 72 and 73, to conductors 14 and 16; conductor 14 extending by way of armature 19 and its resting con tact, armature 23 and its resting contact, armature 28 and its resting contact, lower left hand winding of the repeating coil R, and the lower winding of relay 38 to ground and conductor 16 extending by way of armature 18 and its resting contact, armature 22 and its resting contact, armature and its resting contact, upper left hand winding of repeating coil R, upper winding of relay 38, and the winding of relay 42 to battery. Relay 38 is differentially wound and therefore does not energize over the above circuit. Line relay 42 however energizes and at its armature 43 completes a circuit forthe slow acting relay 45. Upon energizing, relay 45 completes a holding circuit extending back to line switch C over the following path:

Grounded armature 46 and its working contact, low resistance relay 64, release conductor 15,- bank contact 77, wiper 12, armature 5 and its working contact winding of switching relay 3, interrupter springsof the stepping magnet 10 to battery. It is understood that the above circuit is established before the line relay 7 has had time to decnergize. Relay 64 may be of about ohms resistance and is low enough so that. V

the multiples of the test contact 77 are made. busy to other; rotary line switches. The slow acting relay 45 also prepares a circuit for slow acting relay 51 at its armature 4'7, closes the circuit of the lower winding of the electro-polarized relay 29 at its armature 46, and at its armature 48 closes a contact in a special shunt circuit which shall l e described later on. W hen the line relay 42 of the repeater was energized a bridge was closed across the trunk conductors 78 and 80 which may be traced as follows: conductors T8,.upper right hand winding of the repeating coil lower right hand winding of the repeating coih'conductor 71, armature 44 and its workcontact to trunk conductor 80. Upon the closure of this bridge above traced the line relay 81 of the first selector E is energized in the usual manner and. closes the cirucit of the slow acting release relay Uaon energizin the rela 83 )reJares the e a: first selector for operation 111 the vertical movement, and also closes the associated holding circuit'extending back to the preceding switch, the CllClllh being traceable from grounded armature 84 and its worle' ing contact. resistance 100, release trunk conductor 10, over the previously described holding circuit extending back to the switching relay 3 of the line switch C. It will be seen'that the holding circuit is now supplied with ground from two points, both from the grounded armature 4G in the repeater and from the grounded armature 84 in the selector, and it should be mentioned in this connection that the resistance is approximately equal to the resistance of relay 64 of the repeater D. It follows that the circuitthrough relay 64 will continue to supply approximately one half of the current to the holding circuit after the line has been extended to the selector E and relay 64 will therefore remain energized.

Before proceeding further with the explanation, attention is called to the shunt circuit around the armature 44 and its working contact, which it may be mentioned are the impulse springs of the repeater D which control the operation of the selectorE and succeeding switches. This shunt circuit extends as follows: from the armature 44. resting contact of armature 61 and the said armature, resting contact of armature 66 and the said armature armature 48 and its working contact, and the working contact of armatue 44. The contact of armature 48 is closed, but since relay 64 is energized armature 66 will'be attracted and the shunt circuit will be opened at that point, it being clear from this that the shunt circuit will not interfere with the impulse springs represented by armature 44 and its working contact in repeating impulses. I

Only the eighth, ninth and tenth contact levels of the selector E are shown. It is assumed in the present case that the contacts of the first eight'levels connect with'trunl: lines which terminate in switches of the regular switch train, cnntaets of the ninth l vel (TOnliOCt'Wlth trunk lines terminating in special selectors such as the selector E, while contacts of the tenth level are connected with trunks terminating at recording operators positions. The calling subscriber at substation A will therefore operate his calling device in accordance with the digitO. operation of the calling device a series of ten interruptionsis produced inthe circuit of line relay 42 in the well known manner, which, at each deener-giZat-ion rent-acts its armature 44 to interrupt the circuit of the line relay 81 of the first selector E. At the first deenergization of relay 42 an impulse of current is sent through the winding of the slow acting relay 5L Relay ture 119 and its working contact, places the back bridge relay 126 in'bridge of the conductors 1 19 and 150 of the trunk line Z. The trunk lineZ as before explained extends to the office in which the toll recording'operator is located, and the effect of placing back bridge relay 126 in bridge of this trunk line will now be described. ligh resistance relay 168 of the relay group'H is normally included in bridge of the conductors'of trunk line Z'as follows: from the lower conductor 150 of the said trunk line by way of the armature 172 and its resting contact, lower left hand winding of repeating coil R, resting contact of armature 167 and said armature, upper and lower windings of relay 168,

ture 169 the following circuit forthe line lamp L: grounded working contact of armature 169 and the said armature, armature 163 and its resting contact, armature 152 and its resting contact to the lamp L and battery.

The operator upon noting the lighted condition of the lamp L inserts a plug of an idle cord circuit, the plug P for example, into jack J and'thereupon the following circuit is closed for relay 154:: from groundby way of relay 15 1, conductor 17?, sleeve side of the jack J, sleeve of the plug P, resistance 176 to battery. Upon energizing, relay 154: closes at its armature 156 a circuit-for relay 1.62 by way of the normally closed contacts controlledby armature 159, and at armature 155 the said'relay closes a circuit'for slow re lay 158. V the circuit of relay 162' so as to include the armature 153 and its resting contact and arn1ature 159 and its working contact. At the same time that the original circuit is closed for relay'162 a circuit is alsocompleted for relay 173 by way of armature 161 and its resting contact. Relay 158, however is ener.

gized shortly after and at armature. 161 breaks the circuit of relay .173. he eiiect 0 t the encrgization oif relay 1.62 will now be described. Upon energizing, relay 162 c);- tinguishes tl'ieilamp L at armature163 and closes a circuit for relay 166 at its armature 16 1. Relay 166, upon energizing, opens a multiple point in the bridge ofthe conductors of trunk line Z for reasons that will be hereinafter described. Returning now to relay 15 1, this relay upon energizing, places ashunt around the greater partof the high resistance winding of relay 168 at armature 157. In the repeater F the effect of shunting mostof the winding of relay 168 of the relay. group H is th at the resistance of the circuit Upon energizing, relay 158 shifts- 01 back bridge relay 126 is=lowered sullicientily to allow thesaid relay to energize. Upon energizing, relay 126 closes at armature 1 1-2 a circuit for slow acting relay 13 1. .Upon

energizing, relay 131 closes at armature 132 and its working contact a multiple point in the circuit of release relay 121. A further result of the energiza tion' of back bridge re.- lay 126 is'that it closes at armature 1 13 and its working contact a circuit for relay 125.

Upon energizing, relay 125 establishes a locking circuit for itself at armature 128, disconnects the lead from the generator Gen.

at its armature 126 and at armature 127.

ed from ground by wayot working contactof armature 128 of relay 121 and the Said armature, primary winding of induction coil 13?, conductor 1416, bank contact 105 over the previously described circuit, through the switching relay 3 ofthe line switch C and thcstepping magnet 10 to the tone bus bar and battery. The tone machine T causes a high frequency tone to be transmitted over the above described circuit through the primary winding of the induction coil 137, which is repeated to the secondary winding of said induction coil which, it will be noted, is included in a loop comprising conductors 138 and 150, left hand windings ot the repeating coil R, conductors 1 19 and 78, right hand winding of repeating coil R, and conductors 78 and 80. p i

The toll recording operator, haying by this time thrown her listening key K is able to hear this tone and is in this manner in formed that the calling subscriber is on a paystation line, and that any connection completed by her must be paid for before conversation is permitted to proceed. The operator now operates her tone cut off key, the operation or this key completes a circuit for relay 151, which upon operating, at armature 152 opens a point in the circuit of lamp L, at armature 153 opens the circuit of relay 162 and at the same time closes a multiple point in the circuit of relay 158. Relay 162 upon deenergizing, at armature 163 opens a point in the multiple circuit of relay 158, at the sametime closing a point in the circuit of lamp L, opens the circuit of relay 166 at armature 16 1', and at armature 165 opens the bridge across the trunk line Z. Re. lay 168 in the said bridge accordingly dco-nergizes and opens ainultiple point in the circuit of relay 5-8, but since the circuit of the latter relay is closed at armature 153 it does not deenergi-ze at this time. A moment With this later the slow acting relay 166 "deenergizes;

.diately energizes again at armature 1'69 closes a multiple point in the circuitoj relay 'here that relay 181 in the repeater F is The operator .Wlli now return the tone cut oil lrey to normal position thereby breaking the circuit of relay 151. .R elay 1.51 upon deenergizing completes the circuit of lamp L at armature 152,- and at armature 153 opens a multiple point-inthe. circuitof relay 158.- at the same time closing the circuit of relay 162 by Way of armature 159 and-its working contact. Relay162 upon energizing, opens. the circuit of lamp 11 at armature163 before the said lamp has become fully lighted, at the same time closing a multiple point in the circuit of relay 158, closes at armature 165 a multiple point in the bridge across the. conductors of trunk line Z, and at' armature. 16 1'closes a circuit for relay 166. Relay 166 upon energizing, opens a multiple point in the said bridge. This however, has no function at this time. It is now seenthat Whenever the tone cutoff key is nientary opening of the bridge across the trunk conductors'of trunk line Z, the operation of which depends up on the time required for the slow acting relay166 to tall back after its circuit is opened. The. inomentary opening of this bridge across the trunk line Z allows the back bridge relay 126 in the repeater F to deenergize momentarily. Upon deenergizing, the back bridge relay 126 opens atarmature 142 the circuit of slow acting relay 181. It may b5 stated slower to fall back than relay 16 6 in'relay group H. Consequently the deenergiza- .ing Contact,

contact and the winning or salt. e a 0-;

tion of relay126 is of not long enough du- :ration to allow relay 131 to deenergize. As a further result ct themonientary deenergization of relay. 126 a circuit is closed at armature 1-13 for the relay 134. T his. circuit extendstrom grounded working contact ct armature 123 of relay 121'and the said armature, armature 128 armz-iture 1 1:3 and resting tobattery. Relay 13%, upon operating. completes a locking circuit for itself at its armature 135 and at its armature. 136 and its Working contact-"places a short .,circuit aroundthe secondary Winding of the in duction coil 137, thereby cutting the tone 1 The calling subscriber and the toll recordcuit being outlined byrthe heavy conductorv In. casegthe, call is intended from" sub operated the final result is a 1no,

' relay .170 may be traced from ground audits Worlcscriber to Whom connection can be extended Without much delaythe toll recording operator functions as. a regular toll operator also and completes the connection. .Assum- .ing that such isthe case, she tells the calling subscriber to. remain on the line While she calls the desired subscriber. T0 dothis the operator inserts the plug P in'a suitable jack and thereafter takes the usual steps 1 required to complete the connection in any well known or desired manner. 7

Since the station A. is equipped With a paystationit is necessary that the operator collect the coin or coins required to pay for the connection before conversation between the subscribers is permitted. The operator will therefore, upon getting a response from .the desired called party, inform him that he is about to receivea long distance call and to; remain on the line."v The operator nowinforms the calling subscriber that she has obtained the desired party and requests the subscriber to deposit the proper coin.

hen the subscriber has depositedfthe proper coin the operator operates the collect key. Upon operation ofthecollect key circuits are closed for relays 170. of therelay group H, relay, 11001 the repeater F, and

relay 10 of the repeater D. The circuit of through springs 18301? the collect key, conductor 160 and the Winding ofrelay 170 to battery. Relay17O upon-operating, at its armature 172 opens a point ingthe bridgeextending across a trunk line Z byway of high resistance relay 168*and at its working-contact connects-the conductor'15O to the conductor 182 which extends Way of springs 1851 of the collect key to the inding ofarelay 178 topositive high potential battery The opening of the bridge eX- and ground. tending acrossthe trunk .line Z "does not however cause. the deenergization' of back bridge relay 126 at this time as the relay 170 in operating, at its armature 171 com pletes a holding. circuit'extending through only, the upper Winding of this relay. The circuit for relayllO- may now be traced from the grounded release trunk conductor lh hflwinding ot'i'el'ay 110, conductor 150. armature 172 audits working contact, aon'i ductor 182, i lrey and the Winding of relay 178 topositive high potential battery and 'gbund.

springs: 1841; of the collect' I ture lll'completes 'a circuit for slow release I relay 113.. 'Theoperation of'relay 113f Zis effective to complete a. local circuit to maintain i'relay 118energi'zed and toconne'ct the highjpotential battery, ayhich is present on the ..conductor to conductors 14,9 and 'l38 b y way ot mt-ares 114 and 116 and their working contacts. This high potential battery now flows over thetrunk'conductors 78 and 80. The current flow ex;- tending over the conductor 78 extends by way of the upper right hand winding of repeating coil B through the winding of high resistance relay 40 to the grounded release trunk conductor 15. Relay a0 operates over this circuit and at its armature 41 completes a. circuit for slow release relay 20. The operation of relay 20 causes tiie conductors 78 and 80 to be extended by way of armatures 22 and 2S and their working contacts to conductors '16 and 14 extending through the line switch C to conductors 1 and 2 of the subscribers line. Tracing them separately from this point the conductor 1 extends by way of springs 7 1 of the paystation mechanism and the winding of the polarized magnet-to ground; conductor 2 extends by way of the switchhook and its upper contact through receiver R, transmitter and through springs 74 and the winding of the polarized magnet to ground.

This latter circuit is not necessary to the proper operation of the magnet, but is eii'ee tive to short circuit the receiver during the collecting operation to prevent a disagreeable click being heard by the calling subscriber. The polarized magnet at the substation A operates to collect 15116001118 and to open the springs 74. to disconnect the paystation from the line. lVhen the polarized magnet at substation A is included in the circuit'with relay 178 at the operators position the current flow is su'liicient to cause this latter relay to also operate. lay 178 is operated to complete a circuit for the lamp L which is lighted to inform the operator that the subscriber has actually deposited a coin and that the collecting operation is being etiected. The operator may now restore her collect key and again operate it in order to check up to see it the coin has been properly collected. Assuming. that it has, springs 7 1 at substation A will be opened and the relay 178 will not be operated and consequently the lamp L will not be lighted, thereby indicating that the coin has been properly collected. Should the deposit of another coin be required the operator will repeat the operations above de scribed. It may sometimes occur that the operator for one reason or another may wish to refund the coin to the subscriber. She may do this by simply operating her refund key, which causes the negative high potential battery to be applied by way of the relay 180 out over the previously traced circuit. The refunding operation is identical in all respects'with that of collecting, with the exception that, since the battery is of negative potential the polarized magnet at the substation will be operated to refund the coin.

relay 121. Relay 121 upon deenergizing,

causes ground to be removed from release trunk conductors 1410 and 15,'causing the deeiiergization of the switching through relays 9st of the selector E and 3 of the line switch C. Relay 94 upon deenergizing, completes the circuit of release magnet 139 whereby the selector E is restored to normal,"

and the switching relay 3 of the line switch 0 deenergizes and "is therefore again'in its normal position. In the repeater F the line relay 118 upon deenergizing, also at its armature 119 opensa point in the circuit of the back bridge relay 126. Since relay 126 normally maintains the high resistance relay 168 in the relay group H energized, this latter relay deen-ergizes, causing the slow release relay 158 tovalso deenergize. A circuittor supervisory relay 173 is now completed, trom working contact vof armature 156 and the said armature, armature 161 and its resting contact, and the winding of supervisory relay 173 to battery. The supervisory relay 173 upon operating supplies ground and battery to the relay 180 in the cord circuitO which operates to light the lamp L to inform the operator that a disconnection is desired.

It may be convenient at this time to mention that .a similar opera'tion of relays 173 and 158 took place when the'circuit of relay 168 was broken while the 'coin was being collected, but at that time the operation was of no utility and the relay 180' and lamp L* in the cord circuit were not operated due to the fact that the operator had her listening key thrown.

.The operator upon noting the lighted condition of the lamp Lhknows that the conversation has been completed and that the subscriber at substation A has replaced his receiver. Accordingly she removes the plug P from the ack J thereby opening the circuit of relay 180 as well as that ofthe relay 15a. Relay 7 180 upon deenergizing extinguisl es the lamp L Relay 15a'upon deeiiergizing, opens atits armature 156 the circuit 0t relays 162 and 17 These two relays accordingly deenergize. Upon deenergizing, relay 162' at its armature 165 opens the "bridge from across the trunk line Z, and at; its armature 16 1, opens the circuit of relay 166. ;Relay 166' 'upon-deenergizing, again til) fill

has access,

scriber transmits the proper series ofcloses a bridge across'the trunk line Z. All the relays in the relay group Hare now deenergized, and the trunk line Z is in condition to be taken for use tor a Subsequent can. 7.

As previously pointed out the'selector E by way of bank contacts in its ninth level to a-group ot'special selectors, such as the selector E. tors are used for extending connections to the trouble and information operators, and are also used to select reverting call switches. These latter-switches as 15 well known are used by calling subscribers of party lines when connections are set up to call other subscribers on the same line. Since only this type of connection has to do with the invention, the manner of setting up connections to trouble and information operators will not be described. In the description which follows it is. assumed'that a reverting'c'all switchot the type disclosed in the Patent 1,553,951, issued to Martin'L; Nelson,'on Sept. 15, 1925, is the type oi switch to which the selector E has access The only change which need be made in the reverting call switch shown in the drawings of the above applicationis to place a resistance such as the resistance 1G0 or 100, in the holding conductor otthis switch. The purpose of this resistance. is to prevent the 'deenergization oi the relay 6 in the repeater-D when-the revertingcall switch is seized, so that impulses may be also transmitted to 'this switch without the deposit of a coin by the calling subscriber being required.

Keeping will'nov-r be t H substation A initiates a call to another subscriber on the same line. Uponthe remov al of the receiver at substation A the line switch p ture, line conductor 2, through the talking equipment ot the calling subscribers station,

C operates to find an idle trunk lineterinmati in a selector, such as the selector. E. The calling subscriberjnow-operates his Ctlillllg device in accordancewith the digit-9. tiine'the ctor E operates in the 1nan site the contacts of the -ninth i," 'ter which the automatic ihuntoperation takes place to select an idle 'ccial selector E". i

Since the selector E-. is

.in exact duplicate of the selector E, the inanner of operation ot -this switch need notbe described in detail. It is sutlicient to say' tlat the calling subscribernow operateshis call'ng device in accordance with the' proper di to pos tiont-he wipers of the selector E opposite a group of contacts to which are connectedreverting call sw tches of the above in ined type. The automatic selection of idle one c; these reve'r g call switches 'talres place, atteifiwlncn 'the calling subt. pulses to cause'thefreverting call .switch to select ringing current or the proper; ire-1 receiver causing the bridge across the These special selecductors rcnt relay V the above explanation. in mind it ained'that the SUbSCIlbQPflt previously described to" position-its the calling line.

The calling subscriber now replaces his trunk line at the repeater D to be opened. It follows therefore that the line reiay in the recarting -call switch deenergizes to bring about the application of ringing current to the called line, 'WlllOll is also the calling line.

The abore disclosed reverting call switch is arranged to alternately transmit ringing current of the proper frequency to operate the bells of bot-i the calling and called subscribers stations. Now since the relay (it in the repeater Dlhas been maintained ener gizeth-the relay 33 is also in operated position, and ringing current flowing -tr ll therevei b :ingconductors of the selectors E and E and of the repeater D, causing the alternatcurrent relay 36 to operate. Relay connectthe leit hand win-dings .ot the re ductors in multiple with the alternating cur- It will be seen theretore that each time ringing current transmitted over the above circuit therelavs 86 and 17 will be actuated to relay the ringing current dir ctly to the called line.

When the calledsubscriberresponds the ringcut oii relay in the reverting call switch is cperatedl If the receiver is removed during a'ringing period the cut oil relay is operated over a dire t :current path extending by way of conductors 78 0f the'i'epeater D, working contact of armature 18 and the said armature, bank contact 73, wiper 113," working contact of armature 6-an d thesaid armaconductor 180, and conductor 80. As soon as the cut of relay operatesthe rela 36 in -the-repea ter l) deenergizes to ln'eal;- the circuit ot relay l'l'. Relay 17 upon retracting iitsarlnatures again permits a circuit tobe completedv through the lino relay 42 1f,

l-io'wcv'er, the called subscriber .IQIIEOVQS his receiverduring silent period the relay 1'? 1s indeenergized COIl-lltlODRHCl therefore the line relay. 42 of the bpeaterllavfll become aener 'isced and the ri cut-"cit 'rela' will be operated over a circuit extending by way of conductor78,wupper-righthand winding oi",

repeating coil It, working contactof urinavthereverting call switch causes groundto be N call switch nowtiowsover the in operating,'at its armature 3T1 completes a circuit 'l'or relay 1? which operates to dis ture andtheIsaidarInature, lower right; handiwindingof :thelrepeatingcoil, armature.

44} and its. working. contact. to the conductor 'j :80. .Thc operation of the cut oiif relay in across the extendedv callingline. and releaserelays of the second selector therefore energize. The release relay 1n opremoved from the release conductors 151 and a result this switch is also restored to normal. I

Relay 3 of the line switch C upon deenergizing again connects up the line relay 7, which, since the called subscriber has his receiver oil the book, again energizes and in the mam ner previously described again causes the seizure of the now restored selector switch E.

The subscriber at substation A, who is the calling subscriber no longer hearing the bell being actuated, will remove his receiver. Conversation may now proceed inthe ordinary manner battery being supplied to both subscribers from the winding of relay 42 and the lower winding of relay 38 ot the repeater D.

When the conversation is terminated the release of the apparatus will take place in the ordinary manner upon both subscribers replacing their receivers. upon the switchhooks. V

The operation of the circuits when the subscriber at substation A sets up a connection to another subscribers line will now be described, and it will be first assumed that a connection of this kind is attempted without depositing a coin. When the receiver is removed at substation A the operations by which the line of substation A is extended through the medium of line switch C and the repeater D to the first selector E are identical with those described in themevious case and will not .be repeated. The operation ot' the selector E by which the connection is extended to a second selector likewise has also been described, and in this case there is nothing new in the operation except that the wipers of the selector E are raised opposite one oi the first eight levels,

in which are terminated trunk lines which extend to second selectors of the regular trunking system. These second selectors are not shown but are simhar in all respects to the selector E with the exception that the resistan e elements 100 are omitted. .As soonas-the selector E positions its wipers on the contacts of an idle trunk line the switching relay 9d energizes in the same manner as previously described, causing the line relay of the second selector to be bridged The line crating connects direct ground to the release trunk conductor, since no resistance, such as Lesa r3 resistance 100 or 100, isvincluded in this case and the relay 64' at repeater D is practically short circuited. This relay therefore deenergizes and at its armature Q6 closes the previously described I shunt circuit aroundv armature lel of relay-42 and its working contact, thereby renderingthe said armature ll' ineffective to. open the bridge across the trunk conductors 78 and SO'when relay 42 is deenergized. hen the, calling subscriber now operates his calling device in accordance with the next digit and produces another series of interrupt-ions in the line circuit, the resulting deenergizations of relay 4E2 will be of no ellect and it will be apparent that the second selector can not be operated. L Y 7 The difference in the two classes of switches used will now be apparent. All of those selectors which are required to be used in extending connections to operators positions, or for completing reverting calls are provided with resistances similar to resistance 100 and 100, while those switches which are used only in connections to subscribers, have the resistance omitted. It tollows that whenever anattempt is made .to use a switch of the latter class under the c rcumstances just described, where no coin has been deposited, the relay corresponding to relay 64 of the repeater in use will be short circuited and will deenergize to disable the operating circuit extending to the switch. ahead, thus preventing further extension of the connection.

A case w iere the calling subscriber at substation A deposits a coin before calling will now be described, and in thisconnection the process of collecting a coin at the termination of the conversation will also be described. The first operation is to deposit a coin in the collect mechanism. This causes the polarized magnet of thecollect mechanism to be connected "from the line 1 to ground- The. coin may be deposited either before or after the receiver is removed. In either case the latter operation brings about the operationot the rotary line switchC whereby the line is extended to an idle selector switch such as the selector E (Fig. 2). Yi/hen the line conductors 1 and 2 are connectechby the operation of line'switch C, with the windings of the relays 4L2 and '38 of the repeater D the ground placed on the line by the deposit of a. coin, imbalances the diilerential relay 38 causing this relay to operate. It may bestated that the polarized-magnet at the substation is of high resistance and does not materially interfere with the transmission of operating impulses or with the talking circuits, but is sufficient -to unbalance and to cause relay 88 t0 energi'ze as above described. Upon attracting its armature39, relay 38 closes a circuit for re lay 56, whlch relay establishes a locking C1 1:

till

Ill)

i the usual manner.

cuit for itself at its armature 60. Relay 56 also grounds the holding circuit extending back to the line switch C at its armature 59, and its armature 61 opensthe shunt'circuit from around the impulse springs represented by armature 44 and its working contact. This latter operation, it will be noted, permits any 01 the switches in the exchange to be operated no matter whether they are provided with resistances,-such as resistance 100 or 100 or not.

The calling subscriber may now operate his calling device in accordance with the digits in the number of the desired station. The selector E will respond to the first digit in the same manner as has already been described, and the second selector and any subsequent selectors (the number de pending on the capacity of the system) and the connector having access to the called line, Will be operated in a well known manner to complete the connection after which suitable ringing mechanism is automatically operated to signal the called subscriberL When the receiver is removed at the called station talking current is supplied to the transmitter thereat by the usual and well known back bridge relay of the connector, which upon energizing reverses the connections of the incoming trunk conductors in The essential elements of a connector used in this type of connection may be found in the Patent No. 1,551,- 597, issued Sept. 1, 1925 to John W'icks, filed January 19, 1920. The direction of current flow in the bridge over the repeater D is therefore reversed causing the electro-polarized relay 29 to energize. Relay29 upon operating, at its armature 32"completes a locking circuit for itself, at its armature 31 shunts out its upper winding, and at armature 30 disconnects, refund battery potential from connection with conductor 68 and connects collect battery to this conductor instead.

When the conversation is completed both subscribers replace their receivers. WVhen the subscriber at substation A replaces his receiver the line relay 42 of the repeater D is deenergized. The deenergization of this relay causes the bridge for maintaining the usual line relay ot the connector switch to be opened at armature 44. It follows that tary circuit is completed from grounded ar- 7 mature 43 and its resting contact, working contact of armature 47 and the said armature and the winding of relay 51 to battery. Relay '51 upon operating,'at its armature 54 completes a lockingcircuit for itself by way of armature 26 and itsresting contact, and at its armatures 52 and 55 and their working contacts shunts out both windings of thedilierential relay 38. Relay 38 deenergizes and at its armature 39 opens the original energizing circuit of slow release relay 56. The relay 51 at its armature 53 also closes a point in the circuit of slow relay 24, this circuit being completed a moment later by the retraction of armature 46 of relay 45. Relay 24upon operating atits armature 27 opens the locking circuit oi relay 56, and at the working contact of the said armature applies ground to the conductor 15, to preventthe release of the line switch G when the ground is removed from the conductor 15 a moment. later by the restoration or the armature 59, at armature 7 26 opens the locking circuit of slowrrelay 51, at armatures 25 and 28 disconnects the talking conductors of the calling line from the left hand windings of the repeating coil, and at the working contact of armature 28 completes an operating circuit for the polarized magnet at the paystation A and for the relay 49 in the repeater D. This circuit may be traced'from positive high potential battery, resistance lamp 70, work ing contact of armature 30 and the said armature, conductor 68, armature 57 and its working contact, winding of relay 49, working contact of armature 28 and the said armature, resting contact of armature 23 and the said armature, resting contact of armature 19 and the said armature, bank contact. 72 and wiper 11 of the line switch C, working contact of armature 4 and the said armature, springs 74 of the paystation device, and the winding of the polarized magnet to ground. The energization of relay 49 causes. the relay 51 to be maintained energized after ground is removed from its holding circuit by the operation of relay 24. The paystation magnet in operating, opens its springs 74 causing the relay 49 to deenergize. Since the circuit of relay 56 was broken upon energization of relay 24, relay 56 now deenergizes and at its armature 57 breaks a second point in the operating circuit of relay 49 and the paystation magnet; The deener'gization of the relay 49 alsoopens the circuit of slow release relay 51 and an instant later this relay also deenergizes, and at its armature 53 opens the circuit ofrelay 24. Relay 24 upon retracting its armatures after a slight delay removes ground from the conductor 15 to permit the line switch, C, selector E and the other selectors (iiot used Ii the eonnectieri to he restored to normal in the usual manner, and to permit the deenergization of relay 6?. The operations just described are-those which usually take place when the coin is being collected. It sometimes happens however, that the paystation magnet fails to operate fully and in this case when the relay 56 deenergizes and opens the operating circuits of relay l9 and the paystation magnet at armature 5. a circuit for relay G2 is closed at its armature 58. The operatii'ig circuit ot' relay 62 is intermittently opened and closed by the interrupter l and therefore periodically closes a new operating circuit for the paystation magnet and the relay 49 at its armature 63; It will be seen that the relay 4:9 and the payst'ation magnet will now receive the high voltage impulses periodically until the paystation magnet finally operates sufticient to collect the coin. The relay 49 operates to maintain the relay 5]. energized to in turn lreep the relay 2% energized, so

' that the line switch C and relay 6? will not be released or the collect circuit opened. When the coin is finally col ected springs T l open as before preventing further energization of the relay 49, consequently a moment later relay 51 deenergizes and at its armature 53 opens the circuit of relay 2%. Relay 2% upon restoring, disconnects the l'iolding ground from conductor 15 to restore the line switch C, selector E'and the other selectors (not' shown) to normal and to permit the deenergization of relay 6? in the manner previously pointed out. telay 67 upon deenergizing, at its armature 68 disconnects the interrupter from the relay 62 to permanently deenergize this relay.

In case the calling subscriber did not answer it will be necessary to refund the deposited coin rather than collect it when the calling subscriber replaces his receiver, and this refunding operation will now be briefly explained.

Since the called subscriber did not answer the polarized relay 29 will not be energized and the negative or refund battery potential will therefore be present on the conductor 68. Now when the calling subscriber replaces his receiver the various relays in the repeater D operate in the manner previously described, but since the relay :29 is not energized negative battery potential will be present on conductor 68' therefore this refund battery instead of collect battery will be transmitted to the polarized relay at substation A to refund the coin. Immediately following the above operations the various relays in the repeater D and the line switch C will be restored to normal in the same manner as previously described.

\Vhat is claimed is:

'1. In a telephone system, a calling subsciberis station provided with coin collect apparatus, a trunk line comprising two in ductively connected sections, means including a pluralityof automatic switches for extending a connect-ion from said station by way of said trunk line to an operatens posi tion, a battery means at said position tor connecting said battery to one section of said trunk, and means in said trunk responsive thereto tor also connecting said battery to the other section to operate said appara 2. In a telephone s vstem, a subscriberl station provided with coin collect apparatus, an automatic switch, a selector switch, a trunk line divided into two inductively related sections and having one end tcrminating in banl: contacts of said automatic switch and the other end terminating in said selector switch, means including said automatic switch and said selector switch for extending a connection to an operators position, relays insaid trunk for causing a metallic connection to be completed between said inductively connected sections, and means including a source of current at the operators position for causing the operation of said relays, said source of current also being efl ective then to cause the operation of said coin collect apparatus.

3. In a telephone system, a subscribers station provided with paystation mechanism and connected with a line terminating in a central exchange, automatic switches, a trunk line extending from bank contacts of one of said automatic switches in said exchange to another of said automatic switches in a distant exchange, trunk lines terminating in the bank contacts of said last switch and extending to an operators switchboard at the distant exchange, means controlled by a subscriber for causing a connection to be set up via said automatic switches and certain of said trunk lines to said operators switchboard, and means tor causing current to be transmitted over said connection from lOO said operators switchboard to said pays-tation mechanism to collect or refund a coin as desired.

In a telephone syst m, a calling subscribers line, a toll line, means including a series of automatic switches whereby said calling subscriber can connect said lines, paystation mechanism at the station on said subscribers line, high voltage current sources of opposite polarity for collecting and refunding deposited coins, a circuit including a high resistance relay, means whereby the operator can connect either of said sources in said circuit, and means controlled by said relay for connecting the said subscribers line in said circuit in parallel with said relay.

In a telephone system, a calling subof opposite polarity for collecting and refunding deposited coins, a circuit including a high resistance relay, a second relay controlled by said first relay for connecting said subscrihe'rs line in said circuit in parallel with, said first relay, and a polarized magnet at said paystation included in the said parallel branch,

6. In a telephone system, a calling subscribers line, a toll line, a :toll ope'rators switchboard, means whereby said calling subscriber can establish a talking circuit between said lines, said means comprising serially related automatic switches, paystation mechanism at said subscribers station, two sources of current at the operato'rs switchboard, and means controlled by the toll'operator for applyingcurrentfrom either of said sources to the line conductors of the calling line to operate said mechanism.

7. In a telephone'system, a calling subscribers telephone line, an operators switchboard, means whereby said calling subscriber can establish a talking circuit between said line and switchboard, said means including serially related automatic switches, repeat ing coils included in said talking circuit, and paystation mechanism at the subscribers station, and means including sources of high potential current at said operators switchboard controlled by the toll operator for collecting or refunding deposited coins, said means also including a relay for switching a portion of the talking circuit from c0nnection with windings ofsaid repeating coil to one of said current sources.

8. In a telephone system, a party line having subscribers stations equipped with paystation mechanisms, means including series of automatic switches whereby a calling subscriber can establish connections to other lines only when a coin has first been deposited in said mechanism, means whereby connections may be established with an operators position without the necessity of a coin being deposited, and means at the eX change whereby a calling subscriber can cause signaling current to be transmitted back on the same line without the deposit of a coin being required and without the assistance of an operator.

9. In a telephone system, a party line having substations provided with paystation mechanism, means including a series of automatic switches whereby a calling subscriber can establish a talking connection with an operator without depositing a coin, means comprising said series of automatic switches and another automatic switch whereby a calling subscriber may cause signaling current to be transmitted to another station on the same line without depositing a coin, and means comprising said first series of automatic switches and another automatic switch for establishing a talking connection subscriber 'to' deposit a coin in associated paystation mechanism and requiring such subscriber to deposit a coin in such mehanism before connection can be completed to other lines,subscriber controlled means for causing signaling current to be traus mitted ba k over the same line to call other stations on the line without requiring the deposit of a coin in said paystation mechamsni.

11. In a telephone system, a party line,"

paystation mechanism associated with each station on said line, a trunk line equipped with a paystation repeater, facilities for establishing talking connections Via said trunk line to another line, means in said repeater for preventing such connection being established unless a coin has been deposited in the paystation mechanism, other automatic switches used for causing ringing current to be transmitted back to said paystation repeater, for signaling other subscribers on the same line, and means in said repeater responsive to said ringing current to also connect said current to the calling line for the purpose set forth.

12. In a telephone system, a multi-party calling line, paystation mechanism associated with each station on said line, subscriber controlled means for setting up con nections to other lines only when a coin has first been deposited in said mechanism, and means for enabling a calling subscriber to directly set up a connection to cause another station on the same line to be signaled without depositing a coin. I

13.' In a telephone system, a calling line equipped with paystation mechanism, means including a trunk line for completing connections to other lines and to an operators switchboard, a paystation repeater in said trunk requiring the deposit of a coin in said mechanism before connections can be completed to called lines, a source of current in said repeater for operating said pay-station mechanism to dispose of deposited coins, means for rendering the paystation repeater inelfective to prevent the completion of calls extended to an operators switchboard even though no coin has been deposited, a source of current at the operators switchboard, and operator controlled means for connecting said last current source to the calling line to operate said paystation equipment.

14. In a telephone system, a calling line, paystation mechanism associated with said line, subscriber controlled means including a. payst-ation repeater for setting up connections to other lines only when a coin has first been deposited in said mechanism, means for enabling a calling; subscriber to directly set up a connection to an operators position without the deposit of a coin being required, operator controlledmeans for then extending the connection to a called line, a source of current at the repeater for operating the mechanism when calls of the first class are completed and a second current source at the operators position for operating said mechanism when calls are extended beyond the operators position.

15. In a telephone system, a subscribers line, a trunk line, an operators switchboard,

means including a series of automatic switches whereby a subscriber can establish a talking circuit over said trunk to said switchboard, an energized relay in bridge of said trunk line for feeding talking battery to the calling line and for maintaining the release of the connection under control of the calling line, a source of current, a se?ond relay for disconnecting said energized relay from connection with said trunk and for simultaneously closing a local holding circuit therefor, contacts on said second relay for connecting said source of currentto the conductors of the calling line to cause the actuation of said paystation mechanism and operatorcontrolled means for causing the actuation of said second relay.

In witness whereof, I hereunto subscribe my name this 6th day of July, A. 1)., 1928.

JOHN WICKS.

Iii) 

